Entrainment trap



Man 3, 1925. 1,528,104

A. F. EWART ET AL ENTRANMENT TRAP Filed Aug. `19, 1924 Evy-.4.

Patented Mar. 3, 1925.

UNITED STATES 1PA-T ENT!" ARTHUR RjiiiwAiviA AND SEYMOUR TERRY, or HoNoLULU, TRRRITORY' or HAWAII.

RTRAINMENT TRAP.`

Apiiiiation ined August is, 1924. seriai No. 732,944.'

To all whom t may concern:

Be it known thatvwe, ARTHUR F. EWART and SEYMOUR TERRY, citizens of the United States, residing at `Honolu`lu, Territory of Hawaii,`have invented certain new and useful Improvements in Eiitrainmeiit Traps; and we do hereby declare thefollowing to be a full, clear, and exact'description ofthe invention, Asuch as will enable others skilled in the art to which it appertains to make and use fthef same.

The inventionrelates to a novel form` of entrainmei'it` trap or save-all adapted to be 'applied to the 1interiorof an evaporator,

vacuun'ipan, or-similarapparatus, for the purpose'l offseparatin'g the liquid entrained, in the vapors, and returning the separated.y

liquid to the lower part of the evaporator,v therebypreventing the loss of the entrained liquid. The new forni of trap is especially designed to be applied as an ancillary element of or attachment for evaporators already inu'se, as well as to be built intoI new evaporators, and to'this end comprises an annular bottom plate, preferably of dishsliape, sloping toward the central opening,

whichbottom plate is of less diameter than the evaporator chamber, Vand is adapted to be secured with Lits peripheral edge in spaced relation from the wall of the *evaporator chamber by suitable brackets, an upper annular plate, spaced vertically Vfrom the lower plate, said plate' being of a diameter such that itsvperipheral edge engages the walls'y of the evaporator chamber, a series of vertiral baflie plates disposed between the top and bottom plates,the bafflesbein'giof Zigzag form, to providea multiplicity of tor` tuous passageways through the trapv from the periphery-toward'pthe center, the zigzag shape of the baffles also providing a very'rv large number of vertical walls' against which the vapors and entrained liquid impinge in passing through the trap, so that the liquids will be arrested and will run down the Vwalls and along the upper surface of the bottom plate until they .are discharged through a suitableconduit connected with the central opening voftheV bottom plate, said conduit ultimately delivering the liquid to the lower part ofthe evaporator chamber. yIn order tov increase the retarding effect of the zigzag baffle plates, the latter are provided at their elbows or `exterior `angular edges, with curved extensions which, in effect, constitute pockets which tend to set up awhirlng niotion in the vapors, whichwill further assist" in separating the liquid from'the vapors, the lower'edg'es of the curved extensions ter-v minating short of the "bottom platetd'pr'oL'.

F l'is a vertical section through thev upper part of a typical evaporator, having the entrainmenty trapv applied thereto.

Fig. 2 is a plan 'view with the top of thev evaporator chamber removed and the upper:

plate of the trap broken away, in part. Y v

y Vvide escapel 'openings4 kfor the separatedliquid and permitf the latter to run freely' Referring to the drawings, l indicates the l body or shell of a standardk evaporator or vacuum pan, which is generally cylindrical vin shape, and is provided with a generally 'frusto-conical top section 2 having the usual" discharge opening 2 at the top. In the op! eration 'of an apparatus of this general type, commonly used inL sugar boiling andsimllar operations, ay relatively large amount of the' liquid is entrained by and carried ofl inthe vapors, unless specific means are pro'-v froml the vapors.' arious 'forms of savealls and entrainment traps have been ydevisedl'ieretofore' for this purpose, but'in vfmostcases they save-alls have involved eX- pensivey andmore or lesscomplicated cony structions formed as component parts of the evaporator, andthereby making it difficult' tov` clean orrepairithefsame. The vinstant invention provides an entrainment trapA which `may be readily applied to any of the:

standard'types ofevaporators at a minimumv ycost of'laborand materials, but which will .nevertheless produce quite as effective results'as the more expensive and older types. of save-alls.

As shown in the drawings, theentrainment trap is adapted to be installed within vided for separating the entrained' liquid the upper part of the evaporatork chamber,

in such manner that the rising vapors vcari-ying the' entrained liquid will be caused vto pass laterally over the bottom of the trap, thence inwardly through the trap by way of a series of tortuous passages wliichypro duce rapid changes in direction of flow of the vapors, aiidpresent a large` number of vertical walls againstv whichthev vapors im'- pinge, the change`v of' Idirection and impact A of the vapors being veffective in arresting andv throwing out the entrained liquid. The trap proper comprises a bottom plate 3, preferably being slightly dished or concaved toward the center and terminating in a downwardly turned peripheral edge portion Ll which materially reinforces the bottom plate and acts as a collecting chamber Yfor entrained liquor, and also serves as a ready means for attachment of the brackets 5, by means of which the trap is supported within the evaporator chamber. A pipe connected to the chamber formed by the peripheral edge portion et serves to drain the liquid collected in said chamber bach into the evaporator chamber. The diameter of the bottom plate 8 is less than the interior diameter ot' the evaporator chamber, thereby leaving an annular space for the passage of the vapors rising in the chamber. The center of the bottom plate 3 is provided with an opening 6 below which is secured a union 7, from which leads drain pipe 8, which may terminate at any desired point in the lower part of the evaporator chamber. A

upper annular plate 9, having an enlarged central opening lO, is spaced vertically from the bottom plate 3 by a series of vertical zigzag baiile plates 11, connected to the respective plates in any suitable manner, and forming a series of tortuous passages extending in a general radial direction trom the periphery of the trap toward the center' thereo1. rlhe peripheral edge of the top plate 9 engages the walls of the evaporator chamber, so as to prevent the escape of vapor between said peripheral edge and the wall of the chamber.

Preferably the battlel plates 11 are provided at their vertical angles, or meeting edges, with curved extensions 12 which constitute additional obstructions to the flow of the vapors through the trap and are etlective in setting up vertical whirls of the vapors as the latter pass through the tortuous channels or passages between the battles. The lower ends of the curved extensions 12 terminate short of the bottom plate 3 to permit the liquid separated from the vapors to escape from the pocket-like elements formed by the said extensions 12.

F rom the foregoing description, it will be apparent that the vapors generated in the evaporator, and carrying the entrained liquid, upon reaching the entrainment trap, will be deflected by the lower face ot the bottom of the trap outwardly towards the walls of the chamberl 1, thence inwardly through the trap, where said vapors follow the zigzag passages formed between the battle plates, whereby the vapors are caused to change their direction of flow and are also caused to impinge with more or less violence against the vertical walls of the baiile plates, which will have the effect of arresting the entrained liquids which flow down the vertical walls and onto the bottom plate, whence they are discharged through the central opening 6 therein, and will be carried off by the drain pipe 8 to the lower portion of the evaporator chamber. As hereinbeitore indicated, the curved eXtensions 12, located on the elbows or angular joints of the baiiie plates, will be further effective in separating the entrained liquid by setting' up whirling movements in the currents ot vapor passing through the tortuous passages, the liquid which is arrested within the curved extensions escaping through the opening 13 between the bottom edges oi said extensions and the top surface of the bottom plate 3.

Vvlhat we claim is:

l. An entrainment trap for evaporators comprising an annular bottom plate of less diameter than the evaporator chamber, a vertically spaced annular top plate the peripheral edge ot' which is adapted to engage the wall of the evaporator chamber,

zig-zag vertical baffle plates disposed bei tween and engaging the top and bottom plates forming a series of tortuous passages from the periphery towards the center of the trap, and a conduit connected to a central opening in the bottom plate to return the separated liquid to the lower part of the evaporator cha er.

2. An entrainment trap for evaporators comprising an annular dish-shaped bottom plate of less diameter than the evaporator chamber, a vertically spaced annular top plate the peripheral edge of which is adapted to engage the wall of the evaporator chamber, zig-zag vertical baffle plates disposed between and engaging the top and bottom plates forming a series of tortuous passages from the periphery towards the center o1" the trap, and a conduit connected to a central opening in the bottom plate to return the separated liquid to the lower part ot the evaporator chamber.

3. An entrainment trap for evaporators comprising an annular bottom plate of less diameter than the evaporator chamber, a

vertically spaced annular :top plate the pev ripheral edge of which is adapted to engage the wall of the evaporator chamber, zig-Zag vertical batlie plates disposed between and engaging the top and bottom plates forming aseries of tortuous passages from the periphery towards the center of the trap, said ballie plates having curved extensions at their exterior angular edges, and a conduit connected to a central opening in the bottom plate to return the separated liquid to the lower part of the evaporator chamber.

1l. An entrainment trap for evaporators comprising an annular bottom plate of less diameter' than the evaporator chamber, a vertically spaced annular top plate the peripheral edge of which is adapted to engage the wall of the evaporator Chamber, zig-zag vertical baille plates disposed between and engaging the top and bottom plates forming a series of tortuous passages from the peripherjt7 towards the center ofthe trap7 said baffle plates having curved eXtensions at their exterior angular edges terminating short ot' the bottom plate, said battle plates having curved extensions attheir eK- terior angular edges, and a conduit connected to a Central opening in the bottom plate to return the separated liquid to the lower part of the evaporator chamber.

5. An entrainment trap for evaporators comprising an annular bottom plate of less diameter than the evaporator chamber, brackets for supporting said plate yin spaced relation within said chamber, a vertically spaced annulartop plate the peripheral edge of which is adapted to engage the wall of the evaporator Chamber7 zig-Zag vertical battle plates disposed between and engaging the top and bottom plates forming a series of tortuous passages :troni the periphery towards the center ot the trap, and a conduit connected to a central opening'in the bottom lplate to return the separated liquid to the lower part otl the evaporator chamber.

In testimony whereof we affix our signatures.

K'ARTHUR F. EVART.

SEYMOUR TERRY. Witness:

J. J. MACGARVEY. 

